The training group behind a "zombie apocalypse" exercise ripped by Republican Sen. Tom Coburn (R-OK) pushed back against his criticism, KNSD-TV reported Friday.

"It's been insinuated that Homeland Security and taxpayer money was used to fund the summit and that's where we are seeing the most backlash," said Halo Corporation spokesperson Sandy Moul. "That was not true; it was completely funded by strategic operations that produced that demonstration."

Earlier this week, Coburn singled out the exercise, put on during a Halo "counter-terrorism summit" event in San Diego on Halloween, in a 54-page report he released on wasteful expenses incurred by the Department of Homeland Security (DHS).

According to The Huffington Post, Coburn questioned why money from homeland security programs like the Urban Area Security Initiative was going to fund an event held at a luxury report, in what amounted to a sales opportunity for security contractors paid for by taxpayers.

Coburn also criticized DHS for spending $35 billion on things like a $98,000 dive robot for DHS officials in Ohio and $6,200 on a Michigan request for sno-cone machines to treat heat-related illnesses, among other projects.

In a statement, Coburn's office told the station events like the zombie exercise "represent what's wrong with Homeland Security and Congress' failure to have proper oversight. Among all the threats we face, the zombie apocalypse is low on the list."

The company said Coburn did not contact it to discuss the issue, and that the exercise was actually put on by an outside sponsor.

"We absolutely stand by its value," Moul said. "It was a great simulation of a biological and chemical-weapon mass-casualty exercise, and it was great for the first-responder and law enforcement attendees to be able to see some of the techniques used for triage, decontamination and other medical procedures."

Watch KNSD's report on the dispute surrounding the exercise, aired Friday, below.

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